Symptoms and Impacts in Metastatic Castration-Resistant Prostate Cancer: Qualitative Findings from Patient and Physician Interviews.

BACKGROUND: There is little information available on health-related quality of life in patients with chemotherapy-naïve metastatic castration-resistant prostate cancer. This study aimed to develop a conceptual model that describes patients' experiences of living with this condition.

METHODS: This was a cross-sectional, non-interventional qualitative research study. Sixty-minute semi-structured interviews were conducted with physicians experienced in treating metastatic castration-resistant prostate cancer and with chemotherapy-naïve patients with metastatic castration-resistant prostate cancer. Interviews were audio-recorded and transcripts were analysed to identify the key symptoms and impacts on quality of life. Results were used to expand a previously published conceptual model for non-metastatic castration-resistant prostate cancer.

RESULTS: Three physicians and 19 patients with metastatic castration-resistant prostate cancer were interviewed. Physicians identified several symptoms frequently mentioned by their patients: fatigue, bone pain, anxiety, stress, depression and interference with daily activities. The most salient symptoms emerging from the patient interviews were urinary frequency and urgency, fatigue, pain/stiffness and sexual dysfunction. The most salient impacts were interference with daily activities, frustration, anxiety and sleep problems. Compared with non-metastatic castration-resistant prostate cancer, some symptoms and impacts in metastatic castration-resistant prostate cancer were more common and rated as more disturbing (e.g. fatigue, pain, urinary frequency, interference with daily activities and frustration). New concepts that were added to the non-metastatic castration-resistant prostate cancer model, to more accurately reflect the experiences of patients with metastatic disease, were enlarged breasts, muscle loss/deconditioning, inability to focus/mental slowing, body image perception, interference with work and lack of ambition/motivation.

CONCLUSIONS: Chemotherapy-naïve patients with metastatic castration-resistant prostate cancer experience a substantial burden from their condition. Furthermore, as castration-resistant prostate cancer progresses from the non-metastatic stage to the early metastatic (pre-chemotherapy) stage, certain symptoms become more common and disturb patients' lives to a greater extent. The resulting conceptual model for metastatic castration-resistant prostate cancer highlights areas that are not adequately assessed with current patient-reported outcome instruments.